Can someone explain why oxygen is 120 degree angle and not109.5? I thought oxygen hybridization is sp2 with one lone pairwhich would make the structure bent to be 109.5 degrees.

5. What are the expected bond angles at the oxygen and carbon atoms in bold in the structure shown? || H3C-O-C-CH3 A. 109.5 at oxygen, 109.5 at carbon B. 109.5 at oxygen, 120 at carbon C. 120 at oxygen, 109.5 at carbon D. 120 at oxygen, 120 at carbon E. 180 at oxygen, 109.5 at carbon F. 180 at oxygen, 120 at carbon