Read the following statements - Assertion (A) and Reason (R): Assertion: The marginal product of a factor input initially rises but after a certain level, it starts falling. Reasoning: Initially, with increase in amount of the variable input, the factor proportions become more & more suitable for production. After a certain level, the production process becomes too crowded with the variable input. From the given alternatives choose the correct one:

Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of Assertion (A). Assertion (A) is true but Reason (R) is false. Assertion (A) is false but Reason (R) is true. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

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

Factor proportions represent the ratio in which the two inputs are combined to produce output. As we hold one factor fixed and keep increasing the other, the factor proportions change. Initially, as we increase the amount of the variable input, the factor proportions become more and more suitable for the production and marginal product increases. But after a certain level of employment, the production process becomes too crowded with the variable input. The marginal product begins to fall.