Even though modals are tenseless auxiliaries, they may convey ideas referring to the past, present or even future. Mark the option in which "could"...

Even though modals are tenseless auxiliaries, they may convey ideas referring to the past, present or even future. Mark the option in which "could" is used to describe a past ability.

 It could be dangerous.

He could not detect any trace of poison.

Harry, could I borrow Hedwig?

Could you have a look in the writing desk in the drawing room and tell us what´s inside it?

It could be something much worse.