Covert the ratios so they are all the same measurement type.
A. 5 feet = 5 x 12 = 60 inches.
The scale becomes 1:60
B. 1:30
C. 12 yards = 12 x 3 = 36 feet x 12 = 432 inches.
The scale is 12:432 = 1:36
D. 1 meter = 39.37 inches.
1 inch = 2.54 cm
39.37 x 2.54 = 99.99 inches
The scale converted to inches becomes 1 :100 inches.
The first number would be the size of the drawing, the second number is the size of the actual object
If you use all 4 scale factors for a real object that is 100 inches:
A would need 100/60 = 1.67 inches.
B would need 100/30 = 3.3 inches.
C would need 100/36 = 2.78 inches.
D would need 100/100 = 1 inch.
The larger scaled drawing would be B.