Crane wind limits

A construction site limits crane work by the wind speed measured at the top of the crane. Table 1 gives the action for each wind speed w in meters per second.

Table 1: The site’s wind rule for crane work (Question 1).
Wind speed w (m/s) Action
w < 10 Normal
10 ≤ w < 15 Caution
15 ≤ w < 20 Stop lifting
w ≥ 20 Secure crane

An engineer wrote the pseudocode in Listing 1 for the rule.

Listing 1: Pseudocode for the crane wind rule (Question 1).
Input: Wind speed w in m/s
Output: Crane action
Start
   If w >= 10
      Output Caution
   Else If w >= 15
      Output Stop lifting
   Else If w >= 20
      Output Secure crane
   Else
      Output Normal
   End If
End

The engineer traces the pseudocode for every wind speed in a test set and compares each output with Table 1. With which test set do all tests pass, even though the pseudocode is defective?

  1. {4, 9.9, 12}
  2. {5, 16}
  3. {22}
  4. {9.9, 10, 14.9, 15}