Which statement is correct? AP and S are isotopes. BQ and T have different proton numbers. CQ and S have different nucleon numbers. DR has a greater proton number than P.

To answer this question, we need to understand the definitions of isotopes, proton numbers, and nucleon numbers.

1. Isotopes: Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom.

2. Proton Number: The proton number, also known as the atomic number, is the number of protons found in the nucleus of an atom. The proton number is unique for each element and determines the identity of an element.

3. Nucleon Number: The nucleon number, also known as the atomic mass number, is the total number of protons and neutrons in an atomic nucleus.

Given these definitions, let's analyze each statement:

A. AP and S are isotopes: Without specific information about the elements AP and S, we cannot determine if this statement is correct.

B. BQ and T have different proton numbers: Without specific information about the elements BQ and T, we cannot determine if this statement is correct.

C. Q and S have different nucleon numbers: Without specific information about the elements Q and S, we cannot determine if this statement is correct.

D. R has a greater proton number than P: Without specific information about the elements R and P, we cannot determine if this statement is correct.

In conclusion, without specific information about the elements mentioned in the statements, we cannot determine which statement is correct.