B

Reasoning: The 2010 ACLS update removed atropine from the algorithm for pulseless electrical activity and asystole; it is no longer recommended in these rhythms [Dabrowska & Telec, 2011, PMID 22026279]. The other statements reflect 2010 guidance: rescuers should activate EMS immediately, resume chest compressions right after a shock without rhythm or pulse check, and use the maximum (or manufacturer-recommended) biphasic energy when the exact dose is unknown or for subsequent shocks [Link et al., 2010, PMID 20956222].