Which sentence has no errors in capitalization?

A.
Sarah said, "First, wet the clay." She picked up a lump, dropped it, and said, "then center it on the wheel."

B.
Sarah said, "First, wet the clay." she picked up a lump, dropped it, and said, "then center it on the wheel."

C.
Sarah said, "First, wet the clay." She picked up a lump, dropped it, and said, "Then center it on the wheel."

D.
Sarah said, "first, wet the clay." She picked up a lump, dropped it, and said, "then center it on the wheel."