To find the missing term in the given diagram, we need to identify the pattern or relationship between the given terms. Let's analyze the given terms:

CK 16 9 JROS 24 19 TXKM ? ?

We can observe the following pattern in the given terms:
- The first letter of each term is an alphabetical sequence (C, J, T, ...).
- The second letter of each term is a combination of the first and third letter of the previous term (CK -> C + K = CK, JROS -> J + S = JS, ...).
- The third letter of each term is the previous term's second letter (CK -> K, 16 -> 6, ...).
- The fourth letter of each term is an alphabetical sequence (K, O, S, ...).
- The fifth and sixth letters of each term are sequential numbers (16, 9, 24, 19, ...).

Based on this pattern, we can determine the missing terms:

CK 16 9 JROS 24 19 TXKM ? ?

- The missing term's first letter should be the next letter in the alphabetical sequence after T, which is U.
- The missing term's second letter should be the combination of the first and third letter of the previous term, which is X + M = XM.
- The missing term's third letter should be the second letter of the previous term, which is K.
- The missing term's fourth letter should be the next letter in the alphabetical sequence after S, which is T.
- The missing term's fifth and sixth letters should be the next sequential numbers after 24 and 19, which are 25 and 20.

Therefore, the missing term is "UXMKT25 20".

Out of the given answer options, option B) 21, 14 is incorrect as it does not follow the pattern observed in the given terms. The correct answer is option A) 14, 21.