= Solution
{c}
For distinct $i,j\ne1$, direct <conjugation> gives
$$
(ij)=(1i)(1j)(1i).
$$
Thus the given star <transpositions> generate every <transposition>. Every <cycle> can in turn be expressed as
$$
(a_1a_2\cdots a_\ell)
=(a_1a_\ell)(a_1a_{\ell-1})\cdots(a_1a_2).
$$
By the <disjoint cycle decomposition>, every <permutation> is a product of <cycles>, hence of <transpositions>, hence of the given star <transpositions>. Therefore
$$
\boxed{\langle(12),(13),\ldots,(1n)\rangle=S_n.}
$$
For $n=1$, the empty <generating set of a group> generates the <trivial group> $S_1$.
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