Find out the word which does not belong to the group

1. What answer will you get if you round off 580895 to the nearest hundred thousands?
500000
600000
580000
5800

Ans: 600000

2. Express 15/100 in lowest terms.
2/5
7/9
3/20
11/21

Ans: 3/20

3. Find out the word which does not belong to the group
Grape
Organge
Potato
Lemon

Ans: Potato

4. Of the 200+ viruses linked to the common cold, what is the most prevalent type?
Rhinovirus
Parvovirus
Herpesvirus
Cytomegalovirusx

Ans: Rhinovirus