Answer:
D.) They must be representative of the population.
Explanation:
In general a sample collected from a set of naturally distributed data set must also follow the bell curve or natural distribution
In other way round it can be said that sample set must have the same characteristics as that of the main set and hence a sample must be representative of the population.
Option D is correct
Answer:
Explanation:Daniel Hockney,Henri Matisse, Leonard Da Vinci
To impress foreign leaders
