Match the following 

1	Waterfall model	a)	Specifications can be developed incrementally
2	Evolutionary model	b)	Requirements compromises are inevitable
3	Component-based software engineering	c)	Explicit recognition of risk
4	Spiral development	d)	Inflexible partitioning of the project into stages

Waterfall Model:

Moving forward compulsorily, it is impossible to go back to previous project phase in waterfall model. Hence, this method is inflexible.

Evolutionary:

The model keeps changing with time and according to requirements. Hence, it is incremental in nature.

Component based:

This model relies on reuse-based approach to defining, implementing and composing loosely coupled independent components into systems.

Spiral:

This model is the most advanced. It includes four phases - Planning, Risk Analysis, Engineering and Evaluation.