Ambiguity with circuit symbols
None of those look like a thermistor symbol to me. The usual schematic symbol looks like this: 



or this: 



Depending on whether the origin of the schematic is US/Asia or Europe respectively. 

Edit: 

Since it's an LDR- no the direction the light is coming from does not normally make a difference to the understandability of the schematic. It's a schematic, not a pictorial diagram. However, in the case where there is a light source closely coupled to the LDR which is part of the same schematic, it's common to show them together as below: 



The symbol shown in the above schematic is the one most commonly used in North America and Asia. The European symbol appears to be more like yours.