Answer: Option A. -> True
:
A
In an electrolytic setup anode is the place where oxidation takes place and cathode is the place where reduction takes place. $O^{-2}$looses two electrons at the anode to form oxygen, where as $H^{+}$gain electron at the cathode to form hydrogen gas.
Oxidation is nothing but loss of electrons and reduction is nothing but gain of electrons.
Electrolysis of water gives oxygen $\left(O_2\right)$gas at anode and hydrogen $\left(H_2\right)$ gas at cathode and it can be separated and stored in cylinders

Answer: Option D. -> All of these
:
D
Strongly heating Potassium dichromate, Potassium Permanganate or Potassium Chlorate gives oxygen gas.
Heating above ${400}^{\circ }C$, the following reactions takes place
$4K_{2}C{r}_2{O}_7\to 4K_{2}C{r}_2{O}_4+2C{r}_2{O}_3+3O_2$
$2KMn{O}_4\to K_{2}Mn{O}_4+Mn{O}_2+O_2$
$2KCl{O}_3\to 2KCl+3O_2$
Thus all of them release oxygen gas on heating above ${400}^{\circ }C$.These reactions can be used in the preparation of oxygen gas in laboratory.

:
Oxyacids of Sulphur which have a Sulphur-Sulphur single bond are called thionic acids. For example, dithionic acid has the structure:

According to the VSEPR theory, what will be the hybridization and the oxidation state for the two Sulphur atoms?
Before we answer that, let us try to learn the nomenclature behind the thionic acids series.
Let us look at the following general structure structure:

Here x is any non-negative integer. If x = 0, then we will get the previous dithionic acid formula. If x = 1, total number of atoms in S – S chain is 3. Then the name of the compound for x = 1 becomes trithionic acid. In case x = 4, then there will be six atoms connected by the S – S chain. Thus, for x = 4, the name of the compound becomes hexathionic acid.
Let us take a look at the terminal Sulphur atoms. They (each atom) are connected to two different oxygen atoms via a double bonds. Also they are connected to an oxygen atom by a single bond (in other words, each terminal S atom shares an electron with a hydroxyl radical). Further, each terminal S atom is singly bonded to exactly one other Sulphur atom. We can see there are 4 $\rho$-bonds, two π-bonds and 0 lone pairs. So according to the VSEPR theory, the terminal Sulphur atoms are $s{p}^3$ hybridized and will show tetrahedral geometry. Oxidation state of the terminal Sulphur atoms will be +5.
For x>0, each of the central non-terminal bridge S atoms will exhibit an oxidation state of 0. These S atoms will also have a tetrahedral geometry but bent shape (since each Sulphur bridge atom has two lone pairs of electrons).

Answer: Option B. -> False
:
B
Oxygen is a colorless, odorless gas required for sustenance of life.