Answer: Option A. -> By producing gametes
:
A, B, and C

Hydra reproduces by forming small buds on its body which later develop into tiny individuals. When mature, these tiny individuals detach from the parent body and become new independent individuals. This method is called budding. Hydra also reproduces by fragmentation. Any small fragment of the body of hydra can grow into a full-grown individual. Both these are asexual methods of reproduction. The most common method is budding. Hydra also reproduces sexually by forming gametes in ovary and testes. 
                        

Answer: Option A. -> Water
:
A, B, C, and D
Pollens are yellow coloured powder-like grains produced by stamens and it contains the male germ cell of the flower. Pollen grains, from anthers, get transferred to the female part of the flower i.e stigma, the process is called as pollination. They germinate there and later fertilization takes place where male germ cells are fused with female germ cells and a zygote is formed. Pollination is of two types: self-pollination and cross-pollination. Pollinating agents are animals such as insects, birds, and bats; water; wind; and even plants themselves, when self-pollination occurs within a closed flower.

Answer: Option B. -> Hydra
:
B

Hydra and yeast can reproduce by budding. Amoeba reproduces by fission. Lizard does not reproduce by asexual reproduction. Spirogyra reproduces by fragmentation.

Answer: Option D. -> Coconut tree
:
D
Amoeba reproduces by fission. Planaria reproduces by fragmentation and bryophyllum reproduces by vegetative propagation. All these three are asexual modes of reproduction. In coconut trees, or any palm trees, pollen from male flowers transfers to female flowers, which develop a fruit with a seed inside. This is sexual reproduction, and it keeps the species genetically flexible.