Answer: Option C. -> It will increase the frequency of homozygous genotypes
:
C
Inbreeding increases the frequency of homozygous genotypes and decreases the frequency of heterozygotes. It may or may not increase the frequency of genotypes that produce a dominant phenotype. The key term here is homozygous vs heterozygous and not dominant vs recessive.

Answer: Option D. -> A - 2, B - 4, C -1, D - 3
:
D
The method of producing thousands of plants through tissue culture is called micro-propagation. These plants are genetically identical to original plant and are called somaclones. Isolated protoplasts of different varieties are fused to get hybrid protoplasts which are grown to form new plants, called ‘somatic hybrids’ and this process is called somatic hybridisation .

Answer: Option A. -> Both A and R are true and R explains A
:
A
Domestication is the process of adapting wild plants and animals for human use.
People first domesticated plants about 10,000 years ago. Today, all our major food crops are derived from domesticated varieties. Cabbage, broccoli, kale, kohlrabi, brussel sprouts and cauliflower have all originated from the same wild mustard plant by the process of domestication and selection over a period of time.

Answer: Option D. -> All of these
:
D
Conventional breeding methods like hybridisation and selection among various crop varieties and wild relatives is one of the methods for breeding crops. The constraint in this method is the limited number of disease resistance genes. Mutation can be induced in the plants to create the desired genetic variation resulting in the formation of a new characteristic that imparts disease resistance, not found elsewhere. Other methods like selection among somaclonal variants and genetic engineering are also useful in developing disease resistant varieties.

Answer: Option B. -> Out crossing
:
B
Out crossing is the crossing of unrelated pure breed animals of different traits within the same breed. When animals within the same breed having no common ancestors on either side of their pedigree up to 4-6 generations are mated. The resultant offspring is known as an outcross. This helps restore fertility during inbreeding depression.
Cross breed - superior males of one breed are mated with superior females of another breed.
Inbreed - closely related animals of the same breed are allowed to mate with each other for 4-6 generations.
Interspecific hybridization - when the male and female animals of two different related species are mated.

Answer: Option B. -> Cross- breeding
:
B
During cross breeding, superior males of one breed are mated with superior females of another breed. Cross-breeding allows the desirable qualities of two different breeds to be combined. The hybrid offspring with desirable traits are chosen and are either used for commercial production or are subjected to some type of inbreeding and selection. Inbreeding helps in the development of stable breeds that may be superior to existing breeds. Many new animal breeds have been developed by this approach. For eg., Hisardale is a new breed of sheep developed in Punjab by crossing Bikaneri ewes and Marino rams

Answer: Option A. -> Done in bisexual flowers to prevent self-pollination
:
A
When performing artificial hybridisation, it is necessary that the stigma is pollinated with pollen collected from a desired male parent. If the flower chosen as the female parent is bisexual, the anthers are removed manually in a process called emasculation. This is done to prevent self-fertilisation in the female parent.

Answer: Option A. -> Homozygosity
:
A
Inbreeding increases the frequency of homozygosity. For example, if we started off with a set of parents such that each have one copy of the gene for increased milk production and one copy of regular milk production, using the punnett square, we can deduce that there is a $25\%$ chance of the progeny being a purely high milk producer carrying both copies of the superior gene. Over time, we can breed individuals that have both copies of the superior gene (MM) thereby ensuring that 100% of the progeny are now superior individuals (as shown in the second Punnett square).

Answer: Option A. -> a - ii, b - iv, c - iii, d - i, e - v
:
A
Disease resistance has been bred into many crop varieties for bacterial and fungal pathogens. Wheat cultivar, has been bred for resistance to diseases like leaf and stripe rust, a fungal disease, that causes a rust like layer to appear on the parts affected. Brassica is resistant to white rust, a disease that causes a white colored rust like layer to appear on plant tissues or causes white blisters on the plant tissues that are above the ground. Cultivars of cauliflower are resistant to black rot. Cowpea is resistant to bacterial blight. A chilli cultivar, Pusa sadabahar that is resistant to the Chilli mosaic virus, Tobacco mosaic virus and Leaf curl virus has been developed.

Answer: Option A. -> Recessive mutation express immediately
:
A
Haploid plants are useful in mutation studies becausea recessive mutation will be observed immediately in a haploid plant as the genotype can be identified from the phenotype. In case of diploid plants,a recessive mutation of a dominant gene will be covered by a corresponding dominant allele and the mutation will not be observed until segregation. So haploid plants are preferred over diploids for mutation study because of their clear/obvious expression.