Final answer:
The backstitch is the most suitable and durable option for attaching metal hardware to material, as it provides the necessary strength for holding heavy items, in contrast to the running, whip, and blanket stitches.
Step-by-step explanation:
To attach metal hardware to material with a permanent hand sewn stitch, the most suitable option would be the backstitch. This is because the backstitch is known for its strength and durability, which is essential when attaching something as heavy as metal hardware. In contrast to the backstitch, the running stitch is not as sturdy, the whipstitch might be used for edging, and the blanket stitch is often used for finishing the edges of blankets and other fabric edges rather than attaching hardware.
When performing the backstitch, you would start by securing the thread on the back side of the fabric. Then, you would bring the needle up through the fabric and hardware hole, move a little forward on the surface, and then go back down through the previous stitch's ending point. This process creates overlapping stitches on the back side of the fabric, resulting in a strong line of stitching that is ideal for the weight and pull of metal hardware.