The principal solution of of $(5+3 \sin \theta)(2 \cos \theta+1)=0$ are
- A$\frac{-\pi}{3}, \frac{2 \pi}{3}$
- B$\frac{2 \pi}{3}, \frac{5 \pi}{3}$
- C$\frac{2 \pi}{3}, \frac{4 \pi}{3}$
- D$\frac{2 \pi}{3}, \frac{7 \pi}{3}$
✓ Correct answer: C
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