= Monodromy of hyperplane sections of a smooth curve
Let $C\subset\mathbb P^r_{\mathbb C}$, $r\geq2$, be a smooth <irreducible> <nondegenerate projective variety> of <dimension> one and <degree> $d\geq2$. Let $U$ be the <open subset> of the <dual projective space> consisting of <hyperplanes> meeting $C$ in $d$ distinct points. The incidence projection
$$
\{(p,H):H\in U,\ p\in C\cap H\}\longrightarrow U
$$
is a $d$-sheeted <covering space> in the complex analytic <topology>. Its <monodromy> is the full <symmetric group> $S_d$.<Sectional monodromy groups of projective curves by Borys Kadets>[Proposition 1.1; Lemma 2.2 and Remark 3.5]{ref}
The incidence space choosing two distinct ordered intersection points is <irreducible>, so the <monodromy action of a covering space> is <two-transitive>. A small <loop (topology)> around an ordinary tangent <hyperplane> exchanges its two nearby intersection points and fixes the others. Conjugating this <transposition> by double transitivity gives every <transposition>, and these generate $S_d$. In particular the action on $k$-element <subsets> is <transitive> for each $0\leq k\leq d$. For a degree-one <projective line>, a transverse section has one point and the corresponding group is the trivial $S_1$.
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