Answer:
La bicicleta
Step-by-step explanation:
THe sentence says this:
when i´m on holidays i like to use _____ because it is low-cost and I like to exercise while traveling.
So the options are:
The car
The plane
The bike
The bus
From the options the only one that owuld make you exercise while traveling would be the bike, or la bicicleta, so that would be the correct answer.