GMAT Test Prep: SC-98425483 GMAT Sentence Correction | TOEFL IELTS GMAT GRE SAT ACT PTE ESL

A shooting dead chickens at airplanes has proved helpful to demonstrate

B shooting dead chickens at airplanes has proved itself helpful as a demonstration of

C shooting dead chickens at airplanes proves itself helpful as demonstrating

D that shoots dead chickens at airplanes proves itself helpful to demonstrate

E that shoots dead chickens at airplanes has proved helpful in demonstrating