What is the meaning of 'of + ~ing' in the following sentence,
"The quickest way of contacting the police station is to use your cellphone."
Does it mean
"The quickest way that we contact the police station is to use your cellphone"
or
"The quickest way for us to contact the police station is to use your cellphone"
or
"The quickest way of us to contact the police station is to use your cellphone"
?
Does "of + ~ ing" have the meaning of an omitted subject not in the sentence?