After months of voyage, Columbus arrived in ______ later proved to be a new continent.
C
注意，本句话并非定语从句，而是宾语从句。因为在介词in后面，应该用what引导的宾语从句，what在宾语从句中作主语。
Whenyou're_____acrisis,itoftenhelpstotalktosomeone.
Itisimportantto________yourskinfromtheharmfulstrongsunlight.