請根據上下文，從四個選項中選出最合適者，完成本段文字之語意與語法，回答第 41 題至第 45 題

In the past, when explorers arrived in a strange place, the first thing they did was to 41 their tents or cook ameal. But nowadays, when explorers arrive in a new place, they log on to their social networking site using a satellitephone. Explorers in the past wrote about their adventures in books which were published months or years later.Nowadays, we 42 a message in seconds.Sites like Facebook and Twitter also help if explorers have a problem. Someone in our group touched a strangeplant and suddenly his skin was red and painful. I asked for 43 on Twitter: “Hand touched a strange plant. It’sred and hot. Any advice?” Minutes later, someone who knew the region 44 , “Probably a Pushki plant. If it is, it’llhurt but it won’t kill you!” In the age of modern explorer, 45 like this really helps to make decisions, andsometimes it even saves lives.