The problem seemed to have no unique solution . . . a silly problem.
Then I had a thought (always a dangerous event):
If the given answer-choices are the only ones available,
. . then there is a solution . . . and the problem is even sillier!
The table above shows the number of consecutive nights that each
of five families stayed at a certain hotel during a 14-night period.
If the Sui family’s stay did not overlap with the Lisa family’s stay,
which of the 14 nights could be a night on which
only one of the five families stayed at the hotel?
From the given clue, Sui's family and Lisa's family spanned the entire fortnight.
There are two possible scenarios.
Here's one of them:
. . . . . . . . . . . . . . .
Thomas' family covered 10 consecutive nights:
. . ranging from [1,10] to [5,14]
If Thomas stayed [1,10], [2,11], or [3,12]
. . all 5 answer choices are eliminated.
Hence, Thomas must have stayed [4,13] or [5,14].
Therefore, the night could have had only one family.
. . [So why tells us about Shawn or David?]