Assertion (A) : A species of wasp and a fig species cannot complete their life cycle without each other. Reason (R) : While visiting wasps come to lay eggs in the fig inflorescence, the flower of wasp gets pollinated in return.

The correct option is: Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Step-by-step Explanation:

1. Analysis of Assertion (A):
Assertion (A) states that a species of wasp and a fig species cannot complete their life cycle without each other. This is biologically true. The relationship between wasps and figs is a classic example of mutualism, specifically a co-evolved obligate relationship. A given species of fig can be pollinated only by its specific partner wasp species, and that wasp species cannot successfully reproduce or lay eggs in any other plant. Because their survival and reproduction are completely interdependent, neither species can complete its life cycle alone.

2. Analysis of Reason (R):
Reason (R) describes the biological interaction that occurs when they meet. A female wasp enters the fig inflorescence (a closed, flask-shaped structure called a syconium) to search for suitable egg-laying (oviposition) sites. While she lays her eggs in some of the ovaries of the fig flowers, she simultaneously deposits pollen that she carried from her home fig, thereby pollinating the fig inflorescence. In exchange for this pollination service, the fig provides the wasp with a safe nursery for its larvae and developing seeds as nourishment. Hence, Reason (R) is true as it details the mutual exchange of pollination and egg-laying space.

3. Evaluating the Connection:
Since the wasp relies entirely on the fig for egg-laying and larval development, and the fig relies entirely on the wasp for pollination to produce seeds, this interaction is the precise reason why they cannot complete their life cycles without each other. Therefore, Reason (R) is the correct explanation of Assertion (A).