Step 1: Understanding the Concept:
Somatic hybridization is a technique where protoplasts (cells without cell walls) from two different plants are fused to create a hybrid cell, which is then grown into a new plant.
Step 2: Detailed Explanation:
The "Pomato" is a somatic hybrid produced by the fusion of protoplasts from a potato plant (\textit{Solanum tuberosum}) and a tomato plant (\textit{Solanum lycopersicum}).
The aim was to create a plant that produces both tomatoes and potatoes on a single plant.
Although the plant was successfully created, it unfortunately did not possess all the desired commercial characteristics for wide-scale use.
Step 3: Final Answer:
The fusion involves Tomato and Potato protoplasts. Hence, option (A) is correct.