The correct answer is option 'C' - Universal.

Explanation:
A shift register is a digital circuit that is used to store and transfer data. It consists of a series of flip-flops connected together in a chain, with each flip-flop storing one bit of data. The data can be shifted from one flip-flop to the next, allowing for serial data transfer.

A universal shift register is a type of shift register that offers different modes of operation. It can accept data either in parallel or in a bidirectional serial manner, and it also has internal shift features. Let's understand each of these modes in detail:

1. Parallel Input:
In the parallel input mode, all the bits of data are loaded simultaneously into the shift register. This means that each flip-flop of the shift register is connected to a separate input line. When the parallel load signal is activated, the data on these input lines is loaded into the flip-flops. This mode is useful when multiple bits of data need to be loaded at once.

2. Bidirectional Serial Load:
In the bidirectional serial load mode, the data is loaded into the shift register one bit at a time. This can be done in either a serial-in, parallel-out (SIPO) or a parallel-in, serial-out (PISO) manner. In SIPO mode, the data is shifted in from a single input line, while in PISO mode, the data is loaded into the shift register from separate input lines. This mode is useful when the data needs to be loaded serially.

3. Internal Shift Features:
A universal shift register also has internal shift features, which allow the data stored in the flip-flops to be shifted within the register. This can be done in either a unidirectional or bidirectional manner. In unidirectional shifting, the data is shifted in one direction only (either left or right), while in bidirectional shifting, the data can be shifted in both directions. These shifting operations are controlled by shift control signals.

By offering these different modes of operation, a universal shift register provides flexibility in data loading and shifting. It can be used in various applications where data needs to be transferred and manipulated in different ways.