# ISTQB question: Statement Coverage and Decision Coverage with loop

I'm learning `ISTQB` and encountering a question about `Statement and Decision coverage` in a sample exam of `ISTQB` org.

Evaluate the following `control flow diagram` and determine the `statement coverage` and `decision coverage` resulting from the execution of the following test cases:

• A-B-D-E-F
• A-B-C

a. 33% statement, 100% decision

b. 50% statement, 50% decision

c. 100% statement, 75% decision

d. 100% statement, 100% decision

As the answer sheet, the `correct one is: C`. I understand why 100% statement , but 75% decision. We have 4 Test Cases:

1. A-B-C (test case 1)
2. A-B-D-E-F (test case 2)
3. A-B-D-A-B-C (test case 3)
4. A-B-D-A-B-D-E-F (test case 4)

So the `coverage percentage` is = the `number of run test cases` / the `total of test cases` = 2/4 = 50%. But it is not the same as the answer - 75%.

Am I understanding incorrectly?

Could you please help me point out what wrong it is and share more ideas on it?