उत्तरी बिहार में स्थित शुष्क पर्णपाती वनों को मुख्य रूप से कौन सी संरचनात्मक विशेषता परिभाषित करती है?

In the context of Dry Deciduous Forests in Bihar, which of the following tree species is specifically noted as being primarily found in the southern part of the state?

Which of the following districts in Southern Bihar is characterized by a denser concentration of dry deciduous forest cover?