Choose the word to fill the gap in these sentences
When a person applies for motor insurance many __________ may be taken into account: their age, their previous claims, the car they drive, even their sex.
arguments
explanations
experiences
factors
If he has not been sleeping well, that would __________ for his lack of concentration.
account
explain
focus
provoke
Accidents at work can often __________ carelessness.
contribute to
lead to
function from
result from
It is very unlikely that the global warming can be __________ by natural causes.
considered
explained
resulted
understood
The __________ of a water filter is to remove undesirable elements while being able to provide a steady flow of water,