The domain name system (DNS) is the component that houses the MX record. The MX record is a type of DNS record that specifies which mail server is responsible for receiving email messages for a domain name.
VLAN is an acronym for virtual local area network, which is a logical subdivision of a network that allows devices to communicate as if they were on the same physical segment. DHCP is an acronym for dynamic host configuration protocol, which is a network protocol that assigns IP addresses and other configuration parameters to devices on a network automatically. SMTP is an acronym for simple mail transfer protocol, which is a network protocol that allows sending and receiving email messages over TCP/IP networks

Near field communication (NFC) is a function that enables contactless payments with a phone by allowing it to communicate with compatible devices within close proximity. If NFC is not working properly, the user will not be able to perform contactless payments with the phone. Hotspot is a feature that allows a device to share its internet connection with other devices via Wi-Fi, Bluetooth, or USB. Bluetooth is a wireless technology that allows devices to connect and exchange data over short distances. USB is a standard interface that connects devices such as keyboards, mice, flash drives, etc

A DHCP lease is a temporary assignment of an IP address and other network configuration parameters (such as DNS and gateway) to a device. The lease is renewed periodically to maintain the assignment.
* Why Not A (A definition of the scope of addresses): The DHCP scope defines the range of IP addresses but is not the lease itself.
* Why Not B (A reservation of an IP configuration): DHCP reservations ensure a specific device always receives the same IP address, but this is not the lease.
* Why Not D (A translation of network names to IP addresses): This describes DNS, not DHCP.
CompTIA A+ Exam Reference: Core 1 (220-1101), Section 2.6, DHCP concepts.

See the answer below in explanation part.
Explanation:
Answer of both steps below.