This is a typical CAA exam question designed to test your decision making and rationalisation skills. You just need to recognise the slightly odd way they are worded and answer accordingly. Get used to the style, the CAA love it. However it can be turned to your advantage as even if you don't know the correct answer you can usually eliminate one option and very often two as plain incorrect - leaving you with the correct one.
As ever, the mantra is RTQ.
Which statement is true concerning squall lines
1) They aren't "only" caused by anything. You know squall lines can occur due to katabatic winds, for instance. ELIMINATED
2) They do offer the most intense wx hazards to aircraft. All the most intense wx hazards can be found in squall liens. It's not suggesting all of the most intensive hazards are there, just that a squall line can contain any of them. A TRS is not an individual wx hazard, its a massive weather system containing all sorts of things including icing and IMC, many of which are also found in a squall line. But this question is Which statement is true concerning squall lines, not TRSs, icing or IMC.
3) They certainly do, but does that mean they have to? Always? An answer that appears to be an absolute or definite statement is always a suspect for close examination. (#1 is in this category too). On first reading of the questions I'd be doubting 1 and 3 straight away because of their absolute answers and rather than seeking to agree with #2 I'd be looking carefully for a way of discrediting it, and in failing to do so conclude it is the most correct of the three.
You have to learn to play their game. It's actually quite a searching way of teasing out your knowledge in what otherwise is no more than a multi-guess questionnaire.
Again, RTFQ!
Last edited by meleagertoo; 11th May 2019 at 15:04.