Okay, let's tackle this question about the synol membrane of the knee joint. First, I need to recall what the synol membrane is. Wait, is that the synovial membrane? Maybe there's a typo. Synol might be a misspelling of synovial.

So, the synovial membrane lines the inner surface of the joint capsule, excluding the articular cartilage. Its main functions are to secrete synovial fluid, which lubricates the joint, and to provide nutrients to the cartilage since cartilage is avascular. The synovial membrane is composed of two layers: the intima and the subintima. The intima has fibroblasts and macrophages, while the subintima has blood vessels and loose connective tissue.

Now, the question is asking which statement is true about it. Let's think about common facts. The synovial membrane is absent on the articular cartilage. It's present in most synovial joints, like the knee. The knee joint is a complex joint with a synovial membrane that's continuous with the bursae. Also, the synovial membrane can be affected in inflammatory conditions like rheumatoid arthritis, where it becomes hyperplastic and inflamed.

If the options were about the presence in the knee, absence on cartilage, or involvement in fluid production, then the correct answer would be the one that states the synovial membrane is absent on the articular cartilage. Let me check possible distractors. Incorrect options might say it's present on cartilage, or that it's a serous membrane (which it's not—synovial is a connective tissue membrane), or that it's only in certain parts of the knee.

Another point: the synovial membrane does not cover the menisci in the knee. Wait, no, actually, the menisci are covered by synovium except where they attach to the tibia. So if an option says the synovial membrane covers the menisci entirely, that's incorrect.

Also, the synovial membrane is not continuous with the periosteum. So if an option says that, it's wrong. The correct answer should be the one that states the synovial membrane is absent on the articular cartilage and lines the non-cartilaginous surfaces inside the joint capsule.

So putting this together, the correct answer would be the statement that the synovial membrane is present in the knee joint and is absent on the articular cartilage. The other options would be incorrect for the reasons mentioned.

**Core Concept**
The synovial membrane (a type of connective tissue membrane) lines the inner surface of synovial joints, excluding articular cartilage. It secretes synovial fluid, which lubricates joints and nourishes avascular cartilage. In the knee, it is continuous with bursae and tendon sheaths but absent on menisci and articular surfaces.

**Why the Correct Answer is Right**
The correct statement is that the synovial membrane is **absent on articular cartilage** and **lines the non-cartilaginous surfaces** of the knee joint. It produces synovial fluid via fibroblast activity and contains macrophages to remove debris. In the knee, it extends into bursae but does not cover menisci entirely (only

✓ Correct Answer: A. Invaginated posteriorly by cruciate ligament