Sure, let's go through each question and find the correct answers:

15. He was arrested for trying to pass _____ notes at the bank.
- A. camouflaged
- B. fake
- C. counterfeit
- D. fraudulent

**Correct Answer: C. counterfeit**
- Explanation: "Counterfeit" notes are fake money that is made to look like real money.

16. This fabric has the _____ of silk but it’s very cheap.
- A. stroke
- B. substance
- C. friction
- D. texture

**Correct Answer: D. texture**
- Explanation: "Texture" refers to the feel or appearance of a surface or fabric.

17. I threw some biscuit _____ on the ground and a whole load of pigeons swooped down and started eating them.
- A. grains
- B. specks
- C. flakes
- D. crumbs

**Correct Answer: D. crumbs**
- Explanation: "Crumbs" are small pieces of food that fall off, especially from baked goods like biscuits.

18. The insects looked and tasted so horrible, I _____ with disgust as I tried to force them down.
- A. gloated
- B. grinned
- C. grimaced
- D. chuckled

**Correct Answer: C. grimaced**
- Explanation: "Grimaced" means to make a facial expression of disgust or pain.

19. Going down white-water rapids in a canoe must be extremely _____! Does your heart start beating really fast?
- A. trivial
- B. mundane
- C. sedentary
- D. exhilarating

**Correct Answer: D. exhilarating**
- Explanation: "Exhilarating" means very exciting and thrilling.

20. Was it always an _____ of yours to play for France?
- A. urge
- B. adoration
- C. anticipation
- D. aspiration

**Correct Answer: D. aspiration**
- Explanation: "Aspiration" means a strong desire to achieve something.

So, the correct answers are:
15. C. counterfeit
16. D. texture
17. D. crumbs
18. C. grimaced
19. D. exhilarating
20. D. aspiration