D. None of these
Explanation :
• The minimum number of spectators who are fans of all 5 teams cannot be determined with the given information.
• The percentage of fans of each team is given, however, the total number of spectators is not known.
• Therefore, without knowing the total number of spectators, we cannot determine the minimum number of spectators who are fans of all 5 teams.
• Hence, the answer is None of these.

To find the minimum number of spectators who are fans of all 5 teams, take the difference from 100 from each, and the difference from 100 again for the total
100-90=10
100-85=15
100-70=30
100-75=25
100-80=20
total = 100
100-100=0
Minimum no. of spectators who are all 5 teams' fans= 0