The phrase "a decisive choice" is correct and usable in written English.
It can be used when referring to a choice that is significant and has a strong impact on the outcome of a situation.
Example: "After much deliberation, she finally made a decisive choice that would shape her future."
Alternatives: "a critical decision" or "a pivotal selection".
The delegation, officials said, bluntly warned Pakistan that it faced a decisive choice between fighting alongside the United States — or watching as American forces act alone against the extremist Haqqani network, even inside Pakistan, if necessary.
Or a Paul Ryan administration, for that matter: Many conservatives are eager to see their party's leading champion of entitlement reform enter the race, the better to make 2012 feel like a true hinge-of-history moment, a decisive choice between social democracy and free-market capitalism.
From this last miserable redoubt, at 8.26 p.m. on Saturday, Iraq time, the man who sent hundreds of thousands of Iraqis to their deaths at the battlefront and the torture chambers and the gallows made a decisive choice for life, his own.
In a similar vein, Jerry Walls has spoken of the damned making a decisive choice of evil (see Walls 1992, Ch. 5).
It is concluded that although the problem is complex, the relative costs of competing technologies are not prohibitive, but comparable, leading to an inability to make a decisive choice and delaying progress.
Hence, the patient is faced with a decisive choice: he/she can either undergo HSCT with a good probability of cure but a high chance of death or continue to rely on conventional transfusion and chelation therapy.
When I was sick I chose (and it was a very active, decisive choice) optimism in the form of Silver Linings.
"It was a cause, and I was distrustful of causes," he tells us, "but it was also a choice, and I found my admiration for decisive choice increasing, because I was so essentially indecisive myself".
Among the more recent generations, Mr. Jabbar, now snowy haired, made the most decisive choice.
Still, he made the decisive choice not just to make peace with the former insurgents but to pay them not to fight us.
Mr Morales will then face what might be the decisive choice of his presidency.Correction: we coloured the region of Tarija green on the original map.
