About linear programming problem (LPP), which of the following statements are correct?

(A) In a LPP, the linear inequalities or restrictions on the variables are called linear constraints.
(B) If the feasible region for an LPP is unbounded, then the maximum or minimum value of the objective function $Z = ax + by$ never exists.
(C) The feasible region for an LPP is always convex.
(D) The common region determined by all the linear constraints of an LPP is called the feasible region.

Choose the correct answer from the options given below:

(A), (C) and (D) only

The correct answer is Option (2) → (A), (C) and (D) only

(A) In a LPP, the linear inequalities or restrictions on the variables are called linear constraints. ✔

(B) If the feasible region for an LPP is unbounded, then the maximum or minimum value of the objective function $Z=ax+by$ never exists. ✖ (incorrect; it may still exist for some directions)

(C) The feasible region for an LPP is always convex. ✔

(D) The common region determined by all the linear constraints of an LPP is called the feasible region. ✔