Which would you prefer; earthquakes or planes flying into buildings?

You don't have earthquakes in Australia very often,  do you? 

We do, just not big ones. We had a little tremor in Adelaide a fortnight ago. Wouldn't have been noticed in California or Japan. 

Right and with earthquakes all the buildings would be toppled over so be nothing for the terrorist planes to fly into.

Terrifying either way.

Do the places along the San Andreas fault have special regulations and supervision to ensure quake-proof engineering?
And if so, how long have the laws been in place?
Are the regulations updated according to advances in technologies?

I live on the west coast but far away in Canada and I am not that sure what regulations there are and how such enforcement is applicable. Since some years ago there have been improvements for building codes here and some older structures have  been reinforced or replaced.

So if the buildings are well engineered, that would make most quakes a lot safer than terrorist attacks.

Japan endures hundreds every year with few ill effects.
It's only the really worst ones, like Fukushima, that are a problem. 
And even that one could have been far less tragic if the nuclear power plants had been built to code and properly maintained. In this case, the cultural problem of "face" led to the worst effects.
Also, it should have been forbidden to live or farm below the floodline for tsunamis.

I could have included more choices like pandemics, riots, alien invasions etc. to make it more plain why you should have a choice and not have everything happen at the same time. 

Optimistic, aren't we?