Best way to OR two LED signals
A diode OR using 2 diodes as shown will work.
Either drive line can pull Q1 base low without affecting the other.

Technically it's a diode AND with +ve logic but as our activating signals are active-low i't a diode OR with negative logic.
It could also be seen as a DTL = "Diode transistor logic" AND (or OR) gate.
Long ago you could buy AND gate ICs and this is almost exactly what was inside.
So all your choices are ~~~~~~= the same :-).

This is "best" because it works, is quick and easy and only requires 2 diodes.
Diodes can be about anything.
Usual small diode is 1N4148 but a 1N400x or almost anything else will work.  

In1 / In2 / Out

0 0 0
0 1 0
1 0 0
1 1 1