Given: Statements about linear SHM are to be checked.
Find: Which combination of statements is correct.
Step 1: Analyze statement (A).
In linear SHM, the restoring force is given by F=−kx which shows that the restoring force is directly proportional to the displacement from the mean position. Hence, statement (A) is correct.
Step 2: Analyze statement (B).
Acceleration in SHM is given by a=−ω2x. This indicates that acceleration is always directed opposite to the displacement. Hence, statement (B) is correct.
Step 3: Analyze statement (C).
In SHM, the velocity is maximum at the mean position and zero at the extreme positions. Hence, statement (C) is correct.
Step 4: Analyze statement (D).
Acceleration is maximum at the extreme positions and zero at the mean position. Thus, statement (D) is incorrect.
Step 5: Final conclusion.
Only statements (A), (B) and (C) are correct. Therefore, the correct option is A.