When assembled, the hole ${30}_{0.000}^{+0.030}\text{ mm}$ and shaft ${30}_{-0.020}^{+0.020}\text{ mm}$ will result in:

The correct option is transition fit.

To understand why this is a transition fit, let us calculate the limits of tolerance for both the hole and the shaft.

1. Limits for the Hole:
The basic size of the hole is 30 mm.
The upper limit deviation is +0.030 mm, and the lower limit deviation is 0.000 mm.
Therefore, the maximum hole size is:
$30.000+0.030=30.030\text{mm}$
The minimum hole size is:
$30.000+0.000=30.000\text{mm}$

2. Limits for the Shaft:
The basic size of the shaft is 30 mm.
The upper limit deviation is +0.020 mm, and the lower limit deviation is -0.020 mm.
Therefore, the maximum shaft size is:
$30.000+0.020=30.020\text{mm}$
The minimum shaft size is:
$30.000-0.020=29.980\text{mm}$

3. Determining the Type of Fit:
We compare the extreme conditions of assembly:
- Case A (Maximum Clearance): Occurs when the largest hole meets the smallest shaft.
$\text{Maximum Clearance}=30.030-29.980=+0.050\text{mm}$
Since this value is positive, clearance (looseness) is possible.

- Case B (Maximum Interference): Occurs when the smallest hole meets the largest shaft.
$\text{Minimum Clearance}=30.000-30.020=-0.020\text{mm}$
Since this value is negative, interference (overlap) is also possible.

Because the tolerance zones of the hole and shaft overlap, the fit may result in either a clearance fit or an interference fit depending on the actual sizes of the assembled parts. This is the definition of a transition fit.