The cross bridge cycle starts when _________.A) ATP binds to troponin and is hydrolyzed to ADP and PiB) Acetylcholine diffuses a
way from the synaptic cleftC) Ca2+ is actively transported into the sarcoplasmic reticulumD) Ca2+ from the sarcoplasmic reticulum binds to tropomyosinE) Ca2+ from the sarcoplasmic reticulum binds to troponin
