Question

Assertion [A]: The species that invade a bare area are pioneer species 
Reason [R]: In primary succession, lichens or Phytoplanktons invade rocks and water respectively

• A. A and R are correct. R is the correct explanation of A
• B. A and R are correct. R is not the correct explanation of A
• C. A is correct but R is incorrect
• D. A is incorrect but R is correct

Hint:

In ecology, primary succession begins with pioneer species that can survive in harsh conditions and help create an environment for future organisms.

Answer 1

The Correct Option is A

Assertion (A): The assertion states that species that invade bare areas are pioneer species. This is indeed correct. Pioneer species are the first organisms to colonize barren or disturbed habitats. These species prepare the ground for other species that will follow in later stages of succession. Examples of pioneer species include lichens, mosses, and some types of bacteria. 
Reason (R): The reason states that during primary succession, lichens or phytoplanktons invade rocks and water respectively. This is also correct. In primary succession, there is no soil present, and lichens (in terrestrial habitats) or phytoplanktons (in aquatic habitats) are the first organisms to colonize bare rocks or water surfaces. They help in the breakdown of rocks into soil, which is a necessary step for the development of a complex ecosystem.

Since both the assertion and reason are true, and the reason provides a correct explanation for the assertion, the correct answer is (1) A and R are correct. R is the correct explanation of A.