Grignard Reagents React with Oxirane (Ethylene Oxide)to Form 1 ^$\circ$ Alcohols but Can Be Prepared in Tetrahydrofuran Solvent

Multiple Choice

Grignard reagents react with oxirane (ethylene oxide) to form 1 ^$\circ$ alcohols but can be prepared in tetrahydrofuran solvent.Why is this difference in behavior observed?

A) Steric hindrance in the case of tetrahydrofuran precludes reaction with the Grignard.
B) There is a better leaving group in the oxirane molecule.
C) The oxirane ring is the more highly strained.
D) It is easier to obtain tetrahydrofuran in anhydrous condition.
E) Oxirane is a cyclic ether,while tetrahydrofuran is a hydrocarbon.