Question

Photosynthesis is important because (a) It is the primary source of all food on earth (b) It is responsible for the release of \(\mathrm{O}_{2}\) (c) Both (a) and (b) (d) None of these

Short answer

The correct answer is (c) Both (a) and (b), as they correctly state the functions of photosynthesis.

Step-by-step solution

Understanding the options

The first step is to understand each of the provided options. \n (a) contends that photosynthesis is the primary source of all food on earth. This is because through photosynthesis, plants convert sunlight, water, and carbon dioxide into glucose (food) and oxygen. \n (b) indicates that photosynthesis is responsible for the release of oxygen (O2). In the photosynthesis process, oxygen is a byproduct released into the atmosphere when water is split to provide electrons to replace the ones lost by chlorophyll.\n (c) includes both (a) and (b).\n (d) says none of the options are correct.

Combining the knowledge

Since photosynthesis indeed produces glucose (a form of food for plants) which eventually forms the basis of nutrition for animals and humans, option (a) is correct. Also, indeed oxygen is a byproduct of photosynthesis as water is split in its process, hence option (b) too is correct.

Conclusion

Since both options (a) and (b) are correct, therefore the right answer is (c), which includes both.