You need to answer a given question containing a blank (_). Your answer must be one of the two objects mentioned in the question, for example "trophy" and "suitcase". Your answer must not contain a word that is not present in the question. Please don't use articles (e.g., the, a) before the answer.

Tom needed to decide if he wanted to use a homemade remover or commercial remover to remove the wallpaper, the _ version was harmful for the environment.
commercial

The collar fit perfectly on the neck of the dog but it could still not pass through the door of its cage. The _ is small.
door

John cannot see the word written on the dark background but he can clearly see the number because the _ is light.

number