Here are the options that need to be corrected in each question:

1. C - "the Vietnamese" should be corrected to "Vietnamese" (remove "the").
2. A - "organise" can also be "organize" (depending on British vs. American English). However, if sticking to British English, no correction is needed.
3. B - "the Viet Nam" should be corrected to "Vietnam" (no "the").
4. A - "a paper clothes" should be corrected to "paper clothes" (remove "a").
5. C - "on carps" should be corrected to "in carps" (generally, you would use "in" for fish).

So, the answers to correct are:

1. C, 2. No correction (if using British English), 3. B, 4. A, 5. C.