Be careful not to touch the two wires or you'll get an electric shock, for they are in _____

四个短语的意思分别是
in communication:保持联系
in touch :联系,接触；转而；与…联系
in contact:有联系,接触
in effect：实际上(事实上,在实行中)
题中的意思是不要接触那两根电线,否则会触电,因为它们是相互接触的.应选contact
例句：如果那暴露的电线相互接触,就会发生短路现象.
If the exposed wires contact,we shall have a short circuit.