Iwill mark brainliest along with extra when environmental conditions are unfavorable, why is it an advantage for green algae to reproduce sexually? a.) they are multicellular when conditions are unfavorable, which favors sexual reproduction. b.) sexual reproduction produces larger numbers of offspring in less time. c.) sexual reproduction produces offspring that have greater genetic variety and durable zygotes that can green algae species survive unfavorable conditions. d.) sexual reproduction produces multicellular algae instead of unicellular algae. multicellular algae are better able to survive harsh conditions.