A: Those are separate Developer Packs. For 4.5.2, download the .NET Framework 4.5.2 Developer Pack .

Why would you seek out this specific version? .NET 4.5 introduced substantial improvements over 4.0, including:

Download and run the Microsoft .NET Framework Repair Tool . This utility scans your system for corrupted setup registries and repairs them automatically before you re-attempt the installation. Transitioning From .NET Framework 4.5