A．Bartók’s music was considered more sophisticated than other concert-hall music.
B．Bartók’s compositions incorporated music from the local culture.
C．People were familiar with the Romantic elements Bartók included in his music.
D．Bartók’s took advantage of the popularity of ballet there and wrote many new ballets.

A．Large animals require more food.
B．Large animals have fewer offspring.
C．Large animals need more energy.
D．Large animals have greater difficulty staying warm.

A．Animal populations in the Mesozoic era were smaller than previously believe.
B．Oxygen levels in the Mesozoic era were higher than previously believe.
C．Ocean levels in the Mesozoic era fluctuated more than previously believe.
D．Plant life in the Mesozoic era was less abundant than previously believe.