Non-performing Assets (NPAs) of a bank in India is defined as an asset, which remains unpaid by a borrower for a certain period of time in terms of interest, principal, or both. Reserve Bank of India (RBI) has changed the definition of NPA thrice during 1993-2004. in terms of the holding period of loans. The holding period was reduced by one quarter each time. In 1993, the holding period was four quarters (360 days). Based on the above paragraph, the holding period of loans in 2004 after the third revision was ________ days.

The correct option is 90.

Let's break down the logic of the problem step-by-step:

1. Initial State (1993):
In 1993, the holding period for a loan to be classified as a Non-performing Asset (NPA) was set at 4 quarters. The paragraph specifies that this holding period of 4 quarters is equivalent to 360 days.
From this, we can determine the duration of one quarter:
$\text{Duration of 1 quarter}=\frac{360\text{days}}{4}=90\text{days}$

2. Revisions to the definition:
The RBI changed the definition of NPA thrice during 1993-2004 by reducing the holding period by one quarter each time.

Let's calculate the holding period after each of the three revisions:
- First Revision: The holding period was reduced by 1 quarter.
$\text{New holding period}=4-1=3\text{quarters}$
- Second Revision: The holding period was reduced by another quarter.
$\text{New holding period}=3-1=2\text{quarters}$
- Third Revision (final state in 2004): The holding period was reduced by a third quarter.
$\text{New holding period}=2-1=1\text{quarter}$

3. Calculating the holding period in days in 2004:
After the third revision, the holding period is 1 quarter.
Since 1 quarter is equal to 90 days, the holding period of loans in 2004 was:
$1\times 90\text{days}=90\text{days}$

Thus, the holding period of loans in 2004 after the third revision was 90 days.