。
She shuddered at the sight.
Literal
She [topic-は] that scene [object-を] saw [then-て] shuddered.
ぞっとする is a 擬態語 (state mimetic) for shuddering — the cold prickle that runs down your spine at something horrifying, eerie, or revolting. Pairs naturally with 様子 ('scene, sight, appearance'), here capturing whatever the speaker witnessed without naming it. The te-form 見て ('saw and...') chains perception to reaction in a single causal arc. ぞっと on its own can also be intensified to ぞくぞく for a similar but slightly thrilled or feverish chill.