JEE Main 2023 Chemistry question

Consider the following pairs of solution which will be isotonic at the same temperature. The number of pairs of solutions is/are A. 1 M aq. NaCl and 2 M aq. urea B. 1 M aq. and 1.5 M aq. KCl C. 1.5 M aq. and 2 M aq. D. 2.5 M aq. KCl and 1 M aq.