Question

Which among the following do you consider as the best evidence to show that two species of algae are closely related?
A. They both respire and release $C{O_2}$
B. They both are found in the same habitat.
C. They both reproduce asexually.
D. They both have the same type of pigments.

Answer 1

Algae refers to a broad and immensely diversified group of photosynthetic eukaryotic life forms. Algae thrive in moist or watery environments, thus they're common near or inside bodies of water. They share anatomical similarities with another important group of photosynthetic organisms, land plants. However, the similarities end there because algae lack numerous structural elements seen in plants, such as real stems, shoots, and leaves.

Complete answer:
Option A: In the presence of sunlight, algae respire oxygen, and the amount produced via photosynthesis usually surpasses the quantity needed during the day.
Algae photosynthesize in the daytime, absorbing carbon dioxide and emitting oxygen.
They breathe carbon dioxide and consume oxygen during the hours when the sun isn't shining.
So, option A is incorrect.
Option B: Algae can be found in a variety of habitats, including seas, rivers, and lakes, as well as ponds, brackish waters, and even snow.
So, option B is incorrect.
Option C: In algae, both asexual and sexual reproduction are seen. Asexual reproduction is accomplished by the use of spores.
So, option C is incorrect.
Option D: Algae are photosynthetic creatures with chlorophyll as a photosynthetic pigment.
Each class of algae has a unique set of pigment types that distinguishes it from the others.
So, option D is correct.

Therefore, Option D is the correct answer.

Note:
Algae have certain general traits with both plants and animals. Algae, for example, can photosynthesize like plants and have specialised structures and cell organelles found only in animals, such as centrioles and flagella. Algae can be single-cell creatures or multicellular species. Algae thrive where there is enough moisture. Asexual and sexual reproduction are also possible in algae. Spore creation is used for asexual reproduction. Algae are self-contained organisms, yet some can create symbiotic relationships with other living things.