How do data frames and tibbles differ in behavior?

Question $5$Select one or more:

a$.$

Tibbles do not simplify when subsetting only a single column when using $[,].$

b$.$

Tibbles print more nicely than data frames.

c$.$

Data frames print more nicely than tibbles.

d$.$

Data frames do not simplify when subsetting only a single column when using $[,].$