Answer: Option C
Explanation:
These cells are soft because of its function. Gaseous exchange takes place by the help of these cells. Spongy mesophyll cells are covered by thin layer of water and are loosely packed.
This is because, during the day time when the plant is performing photosynthesis these cells allows the carbon dioxide into the mesophyll cells and the oxygen out of the plant body.
In Double Stranded DNA , Adenine pairs with Thymine as we know, it means amount of A = Amount of T. Here A=30% so T=30%
Total will be 100% (for all 4 bases) , left out is 30 % which will be equally divided by Guanine and Cytocine , hence G=20% and C=20%.
A=30% T=30% G=20% C=20%
The answer is covalent! Hope it helps!