Please choose the correct ending to complete the given sentence: BMX: A man wearing a grey shirt introduces a group of bmx riders and a bmx track. the man wearing the grey shirt

Ending1: leads the group, first riding a stationary bike. Ending2: reveals an orange helmet on top of his head. Ending3: explains the location of the stills. Ending4: describes different techniques used in bmx competition while clips of bmx riders performing different moves.

Answer format: ending1/ending2/ending3/ending4