There are eight types of L-section networks. You often see the types (g) and (h) for antenna tuning units (ATUs).
For each type of the network, a forbidden region is defined. Some examples are:
Since the impedance, ZL=R+jX, of your antenna could be anything, or anywhere on the Smith Chart, you must select the appropriate types of the network depending on the antenna you are using, or on the band you are operating, so that the impedance ZL does not fall onto the forbidden region.
Note that if you only have two types, such as (a) and (d) in the above figure, or (h) and (g) in the previous figure, you can cover all the cases assuming the values of the inductance and the capacitance can be arbitrarily large or small.