Select whether the sentence below is a simple, compound, complex or compound-complex sentence

Question

However, when David came to conquer the city with his army, he discovered that the Jebusites got their drinking water from a spring just outside the city walls.
CxCd or Cx

Answer 1

Subordinate clauses:

that the Jebusites got their drinking water from a spring just outside the city walls.

However, when David came to conquer the city with his army,

Independent clause:
he discovered