First two don't make sense.
Third is correct.
Last one would be volume.
The Stigma can be hairy or sticky to trap pollen.
Answer:
Energy Value.
Ignition Temperature.
Volatility.
Flashpoint.
Ease of Liquefaction (critical temperature)
Products of Combustion
I think the answer might be A or B. Not so sure...
When an acid is added to water, hydronium ions stay the same
