1. **Stating the problem:** We need to select a head boy, two deputy head boys, a head girl, and three deputy head girls from a student council of 14 girls and 16 boys.
2. **Understanding the selection:**
- Head boy: choose 1 from 16 boys.
- Deputy head boys: choose 2 from remaining 15 boys (since one is head boy).
- Head girl: choose 1 from 14 girls.
- Deputy head girls: choose 3 from remaining 13 girls (since one is head girl).
3. **Formulas used:**
- Number of ways to choose $k$ items from $n$ is given by combinations: $$\binom{n}{k} = \frac{n!}{k!(n-k)!}$$
- For ordered positions like head boy, since only one is chosen, it's simply $16$ ways.
4. **Calculations:**
- Head boy: $16$ ways.
- Deputy head boys: $$\binom{15}{2} = \frac{15 \times 14}{2 \times 1} = 105$$ ways.
- Head girl: $14$ ways.
- Deputy head girls: $$\binom{13}{3} = \frac{13 \times 12 \times 11}{3 \times 2 \times 1} = 286$$ ways.
5. **Total number of ways:**
$$16 \times 105 \times 14 \times 286$$
6. **Multiplying step-by-step:**
- $16 \times 105 = 1680$
- $1680 \times 14 = 23520$
- $23520 \times 286 = 6726720$
7. **Final answer:** There are $6726720$ ways to choose the positions.
Hence, the correct choice is d. 6726720.
Student Council Selection Bb3988
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