The correct answer is "Slang displays a tone that is too casual"
Slang speak is highly informal, sometimes even offensive. One should never use slang in a business setting because business deals should be kept highly informal and professional. Slang shouldn't be used under any circumstance as it may insult the people with whom we are talking by making it seem that we don't appreciate them or their business endeavors.
True, The dictionary defines outlook as "A point of <span>view."</span>
The arrival of an unwanted thing or person
Something good happened. The best thing to happen to that individual all day
To try and solve a problem or assist in some way
These are idioms
