Answer:
C. 4,000 regular cruises
Step-by-step explanation:
The Break-even point is where the operating income is zero that is, the firm pay theri variable and fixed cost related to opperations.

Where:

As the company has multple product we must solve for the contribution of the mix:
regular: 30
executive: 90
the ratio of sales is 4:1
Thus 30 x 4/5 + 90 x 1/5 = contribution mix
contribution mix:42
At the current sales ratio we expect to make 42 dollar per seat
Now we calcualte for the BEP of the mix:

BEP 5000
Now, we solve for the ratio of sales wich is 4/5 for regular cruises:
5,000 x 4/5 = 4,000