Natalia prints a photo of a covered bridge. The print measures 6 centimeters by 4 centimeters. She wants to resize the photo into the size of a postcard with a length of 15 centimeters. What will be the area of the postcard?

A. 150 square centimeters
B. 60 square centimeters
C. 2.5 square centimeters
D. 24 square centimeters

The original size of the photo is 6 cm by 4 cm, so the area of the photo is 6 cm * 4 cm = 24 square cm.

When resizing the photo to fit on a postcard with a length of 15 cm, the width of the postcard will be proportional to the original width of the photo.

Original width: 6 cm
Original height: 4 cm
Original aspect ratio: 6/4 = 1.5

New width on the postcard: 15 cm
New height on the postcard: 15 cm / 1.5 = 10 cm

Therefore, the area of the postcard will be 15 cm * 10 cm = 150 square cm.

Therefore, the answer is:
A. 150 square centimeters