I would use the latest version of free Partition Wizard
bootable CD which views Logical free space and Primary Unallocated space as the same for resizing purposes.
Boot PW CD, Rightclick on the three smaller partitions to Explore to see if anything is on them or they are empty as they report. If you don't use factory OEM tools or have made your Recovery Disks and know you don't want that partition then you can delete them.
Otherwise rightclick on the first 5.91 gb partition, select Resize, grab it with the mouse by left clicking and drag it to the right end of the free space, click OK.
Next rightclick C, select Resize, slide the right border to the right to take up the remaining adjacent Free Space, click OK. Apply both steps.
You might be able to get Easeus to do these operations by first deleting the Free Space volume in Disk Management so it reverts to Unallocated Space. However be aware that Easeus and all other managers can fail, as can Partition Wizard Home edition. Only Partition Wizard bootable CD has never failed in hundreds of partitioning operations we have helped with here.