Once the destination has been reached the network makes a connection at what layer to connect for transfer or data?
a) network b) data link c) physical d) transport

(C) Physical

Explanation:

 When the destination are selected by the network then, it makes the connection for transferring the data packets by using physical layer.

As, the physical layer is basically responsible for transmitting the data and reception of the data between the physical medium and device.

The physical layer basically provide the electrical interface during the transmission of data. The physical layer in the network basically provide the hardware elements like cable, ethernet and repeaters.  

answer; availability;

the answer to your question would be something called hertz. the unit of measurement called a hertz, which is one cycle per second, is used to measure clock speed. within one cycle, your computer processes, refreshes, or updates itself to the changes that it is going through. in the case of computer clock speed, one hertz equals one tick per second. the clock speed of computers is usually measured in megahertz (mhz) or gigahertz (ghz)