Which of the following statements are true with regard to the production?

(A) In the short run, at least one of the factors of production remains fixed.

(B) In the long run, all factors of production can be varied.

(C) A period can be defined as long run or short run simply by looking at whether all the inputs can be varied or not.

(D) In the long run, factors of production can be classified into fixed and variable

Option 1 -> Incorrect. Statement (D) is false because in the long run all factors are variable, not classified as fixed and variable.

Option 2 -> Correct. Statements (A), (B), and (C) are all true regarding production periods.

Option 3 -> Incorrect. Statement (D) is false as factors cannot be classified as fixed in the long run.

Option 4 -> Incorrect. Statement (A) is true and should be included, while statement (D) is false.

Hence, Option 2: (A), (B) and (C) only -> Statement (A) correctly defines short run as having at least one fixed factor. Statement (B) correctly defines long run as the period where all factors can be varied. Statement (C) is true as the distinction between short run and long run is based on input variability. However, statement (D) is false because in the long run, ALL factors are variable - there are no fixed factors. The classification of factors into fixed and variable only applies to the short run period. -> correct